People magazine this morning quotes 19-year-old Miley declaring, "I'm so happy to be engaged and look forward to a life of happiness with Liam."
Hemsworth, 22, reportedly proposed last Thursday with a 3.5-carat diamond ring in hand.
Miley and Liam met on the set of Miley's 2009 film, The Last Song. They briefly separated in August of 2010 before resuming their relationship about a year ago.
Perhaps in response to the engagement news, Miley tweeted early this morning, "Life is beautiful."
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